Ranging With Ultrawide Bandwidth Signals in Multipath Environments

Abstract

Over the coming decades, high-definition situationally aware networks have the potential to create revolutionary applications in the social, scientific, commercial, and military sectors. Ultrawide bandwidth (UWB) technology is a viable candidate for enabling accurate localization capabilities through time-of-arrival (TOA)-based ranging techniques. These techniques exploit the fine delay resolution property of UWB signals by estimating the TOA of the first signal path. Exploiting the full capabilities of UWB TOA estimation can be challenging, especially when operating in harsh propagation environments, since the direct path may not exist or it may not be the strongest. In this paper, we first give an overview of ranging \ud techniques together with the primary sources of TOA error \ud (including propagation effects, clock drift, and interference). \ud We then describe fundamental TOA bounds (such as the \ud Cramér–Rao bound and the tighter Ziv–Zakai bound) in both \ud ideal and multipath environments. These bounds serve as useful benchmarks in assessing the performance of TOA estimation techniques. We also explore practical low-complexity TOA \ud estimation techniques and analyze their performance in the \ud presence of multipath and interference using IEEE 802.15.4a \ud channel models as well as experimental data measured in \ud indoor residential environments

Georeferencing in GNSS-Challenged Environment: Integrating Uwb and Imu Technologies

“…Most of the RF approaches, including time of arrival (ToA), time difference of arrival (TDoF), or signal loss-based range estimation, can be used for deriving positions from UWB observations (Dardari et al, 2009;Kupper, 2005). Here, we briefly present the concept of two-way time of arrival (TW-ToA) position estimation, which is applied in our system.…”

On Secure and Precise IR-UWB Ranging

“…2) Fine Synchronization: ToA estimation performs a backsearch [31], [32] in a window of duration T BS preceding the rough synchronization point found by coarse synchronization. The back-search window duration T BS should be in the order of the channel spread.…”

Bayesian Localization in Sensor Networks: Distributed Algorithm and Fundamental Limits

“…Times of arrival (TOA) are known to provide more accurate localization especially in ultra-wide band (UWB) systems [6], [8]. The model in (1) is widely adopted to describe these type of observations; possible bias due to non-line-ofsight propagation can be included as discussed in [1], [7].…”